1. Field of the Invention
The present invention relates to a headlight unit. More particularly, to a headlight unit having a virtual pivot center provided at a position different from a supported position to a vehicle body, wherein a lamp body is swung about the virtual pivot center to thereby perform the adjustment of an optical axis.
2. Description of Background Art
A first type of an optical axis adjusting mechanism for a headlight unit for a vehicle is known wherein the whole of a lamp body is swung about a predetermined pivot shaft. A second type of an adjusting mechanism is known wherein a movable reflector is provided in a lamp body and only the reflector is moved. The first type of adjusting mechanism can be realized by a relatively simple configuration and it is widely used in a saddle seat type vehicle or the like.
Japanese Patent Laid-Open No. 2005-280576 discloses a light unit for a vehicle having a configuration such that a pair of support shafts are provided on the laterally opposite side surfaces of a lamp body at a substantially central position thereof and the whole of the lamp body is swung about the support shafts to thereby perform the vertical adjustment of an optical axis.
However, in the configuration disclosed in Japanese Patent Laid-Open No. 2005-280576, the vertical movement of the lamp body is larger with an increase in the distance from the position of the support shafts. For example, in the case wherein another part is provided close to a lens formed at the front end portion of the lamp body, an extra clearance must be preliminarily left between the lens and the surrounding part in consideration of the range of the vertical movement of the lamp body, thus causing design and structural limitations.